Clinical and biologic features of childhood T-cell leukemia with the t(11;14)

Cytogenetic analysis of cells from 622 consecutive patients with newly diagnosed acute lymphoblastic leukemia (ALL) and successful G-banding chromosome studies disclosed seven cases with the t(11;14)(p13;q11) and one with the t(11;14)(p15;q11). Leukemia cells in all eight cases had a T-cell immunophenotype. The t(11;14)(p13;q11) occurred in 6.8% and the t(11;14)(p15;q11) in 1% of T-cell ALL cases (n = 103). The t(11;14) was associated with presenting clinical features typical of T-cell ALL: male predominance (n = 6), age greater than 10 years (n = 3), hyperleukocytosis (white blood cells greater than 100 x 10(9)/L, n = 5), relatively high hemoglobin level (median, 10.8 g/dL), high serum lactic dehydrogenase level (median, 3248 U/L), presence of mediastinal mass (n = 6), and central nervous system leukemia (n = 2). While there were no significant differences in presenting features between T-cell ALL cases with or without the t(11;14), leukemic cells from patients with the translocations were more likely to coexpress CD4 and CD8 antigens (6 of 6 v 35 of 86 cases tested, P less than .05). Adverse events have occurred in six patients: three central nervous system relapses [including the one with t(11;14)(p15;q11)], two secondary acute myeloid leukemia, and one hematologic relapse. Our results indicate that the t(11;14)(p13;q11) occurs exclusively in T-cell malignancies of intermediate- or late-stage thymocyte differentiation. Additional studies are needed to determine the prognostic implications of these translocations.     

The human myeloid cell nuclear differentiation antigen gene is one of at least two related interferon-inducible genes located on chromosome 1q that are expressed specifically in hematopoietic cells

We have previously shown that the human myeloid cell nuclear differentiation antigen (MNDA) is expressed at both the antigen and mRNA levels specifically in human monocytes and granulocytes and earlier stage cells in the myeloid lineage. A 200 amino acid region of the MNDA is strikingly similar to a region in the proteins encoded by a family of interferon-inducible mouse genes, designated Ifi-201, Ifi- 202, Ifi-203, etc, that are not regulated in a cell- or tissue-specific fashion. However, a new member of the Ifi-200 gene family, D3, is induced in mouse mononuclear phagocytes but not in fibroblasts by interferon. The same 200 amino acid region, duplicated in the mouse Ifi- 200 gene family, is also repeated in the recently characterized human IFI 16 gene that is constitutively expressed specifically in lymphoid cells and is induced in myeloid cells by interferon gamma. The 1.8-kb MNDA mRNA, which contains an interferon-stimulated response element in the 5' untranslated region, was significantly upregulated in human monocytes exposed to interferon alpha. Characterization of the MNDA gene showed that it is a single-copy gene and localized to human chromosome 1q 21-22 within the large linkage group conserved between mouse and human that contains the Ifi-200 gene family. The IFI 16 gene is also located on human chromosome 1q. Our observations are consistent with the proposal that the MNDA is a member of a cluster of related human interferon-regulated genes, similar to the mouse Ifi-200 gene family. In addition, one mouse gene in the Ifi-200 gene family and the human MNDA and IFI 16 genes show expression and/or regulation restricted to cells of the hematopoietic system, suggesting that these genes participate in blood cell-specific responses to interferons.     

Human T-lymphotropic virus I-infected T cells constitutively express lymphotoxin in vitro

We have studied the pattern of expression of the lymphokines tumor necrosis factor (TNF alpha) and lymphotoxin (TNF beta) in T-cell lines established by transformation with human T-lymphotropic virus, type I (HTLV-I), the etiologic agent of adult T-cell leukemia (ATL). We report here that nine of nine HTLV-I-infected T-cell lines, established by in vitro infection with HTLV-I, including those with CD4+ or CD8+ as well as CD4-/CD8- phenotypes, constitutively produce high levels of TNF alpha and -beta mRNA and secrete biologically active TNF beta into the culture medium. Similar patterns of expression are seen in six of six HTLV-I-infected T-cell lines directly established from ATL patients. In contrast, several T-cell lines, either uninfected or infected with human immunodeficiency virus I, did not produce comparable levels of the TNF beta. Comparisons of a normal functional T-cell clone before and after infection with HTLV-I show that expression of TNF beta mRNA is induced in the infected cells. The high level expression in HTLV-I- infected cell lines dose not seem to involve perturbation of the TNF alpha/beta genetic loci by proviral integration. A cell line (81-66/45) nonproductively transformed with HTLV-I that produces tat-1 in the absence of viral structural proteins, produces both TNF alpha and -beta mRNA. This suggests that expression of these cytokines could be mediated in trans by the tat-1 gene product.     

Role of prostaglandin E in the biphasic fever response to endotoxin

Biphasic fevers were induced in sheep with intravascular infusions or injections of 4-10 μg (80-200 ng/kg) of endotoxin, whereas monophasic fevers were obtained with doses of 1-2/μg (20-40 ng/kg). A marked increase in arterial blood pressure invariably accompanied the onset of fever; the latency of responses to the higher and lower doses of endotoxins averaged 26 min and 42 min, respectively. Prostaglandin (PG) assays of plasma from the carotid artery and jugular vein during fever episodes revealed a surge of PGE and PGF coincident with the pressor response and the first phase of fever, but PG were not detected in plasma samples taken throughout the second phase of fever. PG measurements of arterial and venous plasma collected at a distal site (hind limb) showed a similar surge of PGE and PGF in association with the early fever response, indicating that intravascular PG synthesis and release represents a generalized systemic response to circulating endotoxin. Carotid arterial infusions of PGE(2) produced immediate monophasic fevers and pressor responses, whereas PGD(2) infusions produced an immediate pressor effect but no fever. Infusions of PGF(2α) or prostacyclin, however, evoked neither fever nor pressor effects. Intracarotid infusions of leukocyte pyrogen (LP) caused monophasic fevers with latent periods of 15-20 min but pressor responses were not seen and neither PGE nor PGF were detected in plasma samples from the carotid artery or jugular vein before or during fever. Indomethacin, a potent inhibitor of arachidonic acid metabolism, blocked fever responses to endotoxin and to LP. These findings implicate PGE as the mediator of the early phase of endotoxin fever and imply a role for another pyrogenic metabolite ofarachidonic acid in the mediation of the second phase of fever, i.e., the phase associated with circulating LP. It is possible that both pyrogenic metabolites are generated within the vascular compartment, reaching thermoregulatory centers of the brain by transfer across the blood-brain interface.     

人外周血树突状细胞的分离与鉴定

目的:体外分离培养并鉴定人外周血树突状细胞,并观察其抗原呈递功能。方法:实验于2005-05/2006-11在南方医科大学南方医院肿瘤中心生物治疗实验室完成。从人类白细胞抗原A2表达阳性的健康人外周血中分离获得单个核细胞。培养5h后洗涤贴壁细胞,加入含有10%人AB血清的RPMI1640培养基,及重组人粒细胞-巨噬细胞集落刺激因子和重组人白细胞介素4,于培养的第1,3,6天对树突状细胞的形态、表型进行分析,并定期检测树突状细胞的纯度与得率。抽取与以上树突状细胞不同来源的其他健康人外周血。经淋巴细胞分离液分离后,获取非贴壁细胞,用含10%人AB血清的1640培养基重悬,加入白细胞介素2继续孵育6d,作为同种异体T淋巴细胞。将树突状细胞分为两组,一组按常规方法培养6d,另一组在培养至第5天时加入黑色素瘤抗原基因A3编码的多肽继续培养24h。在经紫外线处理后的96孔板中,分别加入树突状细胞悬液1×104,5×103,2×103,1×103细胞/每孔,以自身T淋巴细胞作为对照,每孔设3个复孔,分别加入1×105淋巴细胞/每孔。评价树突状细胞刺激T淋巴细胞增殖的能力。结果:①单个核细胞体外培养至第6天,可获得大量、90.81%高纯度的树突状细胞,能够较高地表达21.8?1a、99.0%HLA-DR、63.4?80、18.9?83和80.6?86。②将诱导培养6d获得的两组树突状细胞作为刺激细胞,以不同的浓度与同种异体淋巴细胞混合,均可产生增殖反应;经过黑色素瘤抗原基因A3编码的多肽处理的各种比例的树突状细胞,较相应未经黑色素瘤抗原基因A3编码的多肽处理的树突状细胞激发淋巴细胞增殖的能力明显增强,浓度相对较高的树突状细胞刺激效果最明显,能够强烈地激发同种混合淋巴细胞增殖。结论:得到了一群较高程度表达CD83、CD86和HLA-DR分子、体外可强烈激发同种异体T淋巴细胞增殖的树突状细胞群。